The present invention relates to a method of setting a region to be subjected to red eye correction for correcting a red eye in an image which has been produced in shooting and a red eye correcting method of correcting the thus set region to be subjected to red eye correction into the eye having a pupil of a specified color.
When a human individual is taken by a camera from the front particularly at night using an electronic flash, there is a case that a pupil appears in a deep red or gold color, namely, a red eye phenomenon occurs.
Such a red eye phenomenon is generated by allowing light of the electronic flash to be incident on an eye from the front the pupil of which is in an open state in a dark place, specularly reflected therein and then by recording the resultant state in the image. The red eye phenomenon includes occurrences of the red eye in which the pupil thereof is captured in red and a golden eye in which the pupil thereof is captured in gold (both eyes are hereinafter referred to as “red eye” as a whole).
To deal with the above-described problem, for the purpose of decreasing a degree of an opening of the pupil which causes the red eye, a camera having a function which permits the electronic flash to preliminarily emit light before shooting and then shoots with the electronic flash has been developed. However, such a camera can not fully prevent the occurrence of the red eye and has a serious problem such that the occurrence of the red eye is not fully prevented, complexion of the human individual becomes unnatural with the preliminary emission of light, a special mechanism is required for preliminarily emitting light or the like.
In recent years, various methods for preventing the occurrence of the red eye by digital image processing have been proposed.
For example, Unexamined Published Japanese Patent Application (kokai) No. 5-19382 discloses a photoprinter which performs a red eye correcting method that obtains image data by performing photometry on different points in an original image, designates a red eye region, converts the red eye region to that having a pupil of a specified color and prints the original image on a color paper based on the resultant converted data.
Further, Unexamined Published Japanese Patent Application (kokai) No. 11-73499 discloses a method of adjusting color in digital images in which pixels of a digital image having original color data corresponding to predetermined color and shape characteristics are identified and the original color data of the identified pixels are adjusted to achieve a desired result.
Moreover, commonly assigned Unexamined Published Japanese Patent Application (kokai) No. 10-75374 discloses a red eye extracting method in which an eye region is extracted from a region including an eye designated by an operator and then is evaluated whether it is the red eye or not from hue and chroma in the thus extracted eye region; specifically, a region having hue within a specified range of red color and chroma over a specified value is evaluated as the red eye, as well as a red eye correcting method in which chroma of the eye region evaluated as the red eye is decreased.
However, in the above-described patent application No. 11-73499, the red eye region can not always be identified or, when it is wrongly identified, the red eye correction is not appropriately performed; while, in the above-described patent application No. 5-19382, a method of evaluating and correcting the red eye in a manual way or in an automatic way instead of the manual way is disclosed, but the method is not performed by a combination of both ways thereby leaving room for improvement in operative efficiency.
Moreover, in the patent application No. 10-75374, a specific method of extracting and correcting the red eye is disclosed; however, there is a premise therein that the red eye is automatically extracted so that, when an eye region extraction or a red eye evaluation is not perfectly performed, operations need be repeated from the beginning and otherwise thereby causing a problem that the method is not necessarily of a good efficiency as an overall image processing operation or photographic printing operation.